hi sezgyno
i have different idea about HFSS i skilled in HFSS but i amateur in cst and novice in FEKO and i design bowtie in hfss but we have to many model of bowtie if u ask question in edaboard pls give full data about question and i emphasis that the HFSS the best software for antenna's simulation which base on resonance like microstrip antenna but feko solve by moment and this software useful for balky structure of antenna witch work like wire or waveguide like monopole CDM or horn antenna
i advise u never use feko for microstrip
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